Dielectric thin films are widely used for many applications and may be fabricated using a variety of techniques, which involve depositing a layer of the dielectric material onto a substrate. Often, characteristics of the dielectric can be altered by the addition of a conductive material. One such characteristic is surface plasmon resonance (SPR).
Surface plasmon resonance is often perceived as enhanced reflectivity of the dielectric material, and is exploited in many fields of technology. Resonance of surface plasmons are often achieved by thermally processing a thin film, such that the resulting thin film displays a moderate increase in reflectivity. Thermal processing is not viable for thin films deposited on plastic or cellophane substrates and only a complete thin film sample can be annealed using thermal processing. Consequently, the use of thermal processing to provide surface plasmon resonance limits the application of the phenomenon of surface plasmon resonance.
It is an object of the present invention to eliminate or at least mitigate some of the restrictions in the exploitation of the phenomenon exhibited by existing techniques.